How to Use the Muscle Gain Rate Predictor
Enter your gender, training experience, body weight, and daily calorie surplus to get a monthly muscle gain range based on Lyle McDonald's Maximum Muscle Potential model. Results show low and high estimates along with annual totals.
For natural male lifters: beginners can expect 2–3 lbs/month, intermediates 1–2 lbs/month, and advanced lifters 0.4–1 lb/month. Female lifters gain at roughly half these rates. A 300–500 kcal/day surplus is optimal. Consuming 0.7–1g of protein per pound of body weight is equally important for muscle protein synthesis.
Frequently Asked Questions
Beginners and returning trainees can build muscle while at calorie maintenance or even in a slight deficit (body recomposition), but gains are slower than in a surplus.
Yes — 70–80% of growth hormone is released during sleep. Getting 7–9 hours per night is critical for muscle protein synthesis and recovery.
Yes. These numbers are based on research with drug-free athletes. Performance-enhancing substances significantly change potential rates.